The facade centres on an Ionic portico, above which rises a substantial green copper dome on a tall, peristyle drum.

The dome, topped by a gilt cupola and cross, is a prominent feature of the Edinburgh skyline and terminates the view west along George Street.

In its early years, it was notable for the ministries of two leading evangelicals: Andrew Mitchell Thomson and Robert Smith Candlish.

Thomson also established a strong musical tradition at St George's: this continued with prominent choirmasters and organists, including Alexander Mackenzie.

[1] Robert Adam had designed a church as the centrepiece of the western side of the square; The funds raised by renting pews in advance had proven insufficient, however.

Construction took three years and the first service took place on Sunday, 5 June 1814 during celebrations for the conclusion of the War of the Sixth Coalition.

When Thomson died in 1831, Thomas Chalmers, his effective successor as the leading evangelical, preached his funeral sermon in St George's.

[6] Assisted from 1823 by choirmaster R.A. Smith, Thomson also established St George's strong musical tradition, even holding choir practices at his house.

[8] St George's minister from 1834, Robert Smith Candlish, was second only to Chalmers as a leading evangelical; he was also an enthusiastic promoter of Sabbatarianism.

[12] In the middle of the twentieth century, structural issues began to plague the building and a portal frame was erected to support the dome.

Despite the appeal's success, the extent of dry rot in the building soon became apparent and the congregation entered into negotiations for union with St Andrew's.

[17] During the restoration, homelessness charities, including Shelter, criticised plans to install railings to deter rough sleepers.

[21][16] Ian Gordon Lindsay and William Forbes Gray also note the church's lack of proportion to Adam’s surrounding buildings.

[16] By the time of St George's construction, concerns over cost and the waning popularity of the Adam style meant a new design was sought from Robert Reid.

[22] The facade of the building, facing onto Charlotte Square, centres on a balustraded portico supported by four Ionic columns in antis and accessed a flight of shallow steps.

Each pavilion stands on a base course and contains a rectangular window and oculus within a recessed arch; above this, an empty frieze panel sits between an impost course and the cornice, which is continuous with the portico.

[24] Reid's drawings show plans to include clocks within the faces of the attic storeys and to crown the pavilions with statues of female figures.

[13] The church was able to accommodate 1,600 worshippers, the interior was, prior to conversion, relatively plain though distinguished by a large pulpit in Spanish mahogany by William Trotter.

[4][27][28] The Royal Commission on the Ancient Monuments of Scotland's survey in 1951 found most of the furnishings were then modern while the doors to sanctuary were likely original.

George Hay hailed the facade as a "fine composition" while noting the dome's lack of relation to the rest of the building.